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Parallel sums and norm convergence

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Abstract

LetA andB be the impedance operators of two resistive Hilbert ports. Then theparallel sum ofA andB, denotedA: B, is defined to be the joint impedance of the parallel interconnection ofA andB. We survey some results about the norm convergence of limɛ↓0(A+ɛI): (B+ɛI). By means of several new examples, we investigate the relation between such norm convergence and range inclusion conditions.

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Green, W.L., Morley, T.D. Parallel sums and norm convergence. Circuits Systems and Signal Process 9, 213–222 (1990). https://doi.org/10.1007/BF01236453

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